Cellular telephones are an integral part of society today. A substantial number of people throughout the world have and use cellular telephones. For many people, the cellular telephone is their primary means of communicating, and of receiving and sending information. Individuals use cellular telephones for personal business, and also in the work environment to conduct business matters. Cellular telephones have become a convenient means to take pictures, record events and save and retain information. As technological advancements with regards to the cellular telephone occur, more features are available on the cellular telephone. People easily find new uses for the cellular telephone based on the new features. Many consumers pre-order the latest cellular telephone devices and often, there are long lines of consumer waiting to be the first to have the new devices with the latest technology.
Currently, with all of the new technical developments and the expanded uses for small mobile electronic devices, the cellular telephone industry is going through a major transition. Most of the original usage of cellular phones was voice usage. People used cellular phones to conduct verbal communication. A main type of cellular phone was the “feature” phone. These earlier phones did not have big screens and many of the current features and they were used primarily to make telephone calls. Today, there the ‘smart’ phone. The current cellular phone devices have many more features than original cellular phones. As a result, people are finding more uses for these phones. Further, where the primary use of original cellular phones was voice, today people are using their cellular phone devices to transmit data (i.e. text and images). In fact, usage of cellular phones is becoming more to transmit data than voice. This shift in usage from voice to data is creating a challenging situation for the cellular phone network providers. The original design of cellular networks did not anticipate the increasing transmission of data. The increase in data traffic places a strain on the cellular network operations.
A conventional cellular network configuration 100 shown in FIG. 1 has antennas, radios and logic 192 referred to the ‘Node B’. The cellular telephone devices 104 communicate with and through the cellular network through the Node B. In the cellular network 100, the Node B communicates with the Radio Node Controller (RNC) 106 and 108. One RNC 106 may have connected to it a hundred Node Bs 102. The connection between the Node B and RNC can be through to microwave link 110. Next the RNC connects to the core network 112. The core network 112 can also have several RNCs connected to it. Because these communication links 110 are microwave links, there is a limited amount of bandwidth available to transmit information across these microwave links. These communication links have plenty of bandwidth to transmit voice communications. However, with the increased use of data-driven application's such as browsing the web, texting and watching videos via their cellular phones, the bandwidth on these microwave links is approaching the capacity of use.
The long-term solution is to upgrade the communication links. One upgrade option is to replace the microwave links with fiber. However, this option is incredibly expensive to implement. A second, but more short-term option is to reduce the amount of traffic transmitted across these microwave links. Therefore, there is currently a financial issue associated with the upgrade of the communication links to accommodate the increasing data traffic.
Specially, to address this bandwidth issue, the preference is to reduce the amount of information flowing between the RNC 198 and the Node B 102. Currently, there are some known techniques that one can implement to reduce this flow of information. One technique is caching. Another technique is data compression. However, there are some limitations with the use of these techniques to address the specific problems related to the transmission of data in cellar telephone networks.
The cellular telephone design and the cellular telephone protocols are designed to enable a cell phone user to roam through a cellular network. Referring to FIG. 2, a cellular network 200 is comprised of several little cells 202. A user can transparently move from one cell to another cell. The user is not disturbed as they move between cells. In some locations, such as metropolitan areas, a cellular phone user can be in one location and east switch cell sites every few seconds and not notice. The cellular network addresses all of the switching from one cell to another cell for the user.
If there is a decision to use data compression to address the current data transmission concern, there would be real challenges to using that technology with regards to cellular telephones. The decision is to compress the data packet as it is seat from the RNC to the Node B. In practice, as long as the user receiving the packet remains at the same Node B (cell site), they can receive the entire sent packet. However, if the user moves to another cell site location before all of the pickets are received, the current technology does not know how to route packets to the new cell site location of the use such that the user can continue to receive packets. Currently, the RNC has to route all of the packets to the same cell site in order for the compressed information to be decompressed and sent to the user. Document compression is based on everything that is in the document. If the user moves from tower to another during the receipt of a packet, that packet could be lost. The user could receive another packet at the new cell site location as long as the user stays at the cell site location. However, the user may move through several cell site locations while trying to receive information that is transmitted to the user through antennas at the cell site locations. For example, a user requested document may have 10 packets that need to be sent to the user. The user may be at one cell site location and receive the first three packets. While receiving the fourth packet the user may move to another cell site location. The use would lose the fourth packet. However, the user may stay at the second cell site long enough to receive the filth packet. Even though all ten packets of the information were sent to the user, because the user moved from one cell site to another, the user did not receive all ten packets of the information. Therefore, the transmission of the information was useless.
In another example, a user is watching a movie on cell site ten, if the user moves to cell site eleven, there will be an interruption in the movie because the movie was being streamed to cell site ten. With current technology, moving from one cell site to another cell, site while receiving a packet with cause the loss of data.
The limitation of the current technology regarding the transmission of data to a cell site and to the user requesting the information is that cell sites contain state information about the transmitted data. An example of state information is the packer count of information being sent to a user. When a cell site is receiving the packets of information, the cell site is counting and tracking the information packets being received. During a transmission, the initial cell site may have received packets one, two and three. If the user moves to another well site, the new cell site will start counting and tracking packets. However, there count would also be one, two and three even though that cell site is receiving packets four, five and six. Therefore, the packet count will be inaccurate. When moving between cell sites, the state information regarding that transmission will be in two different cell sites. In order to process the information into a usable form for the user, all of the state information regarding that transmission has to be in one cell site location.
A form of data transmission for fixed devices such as laptops and desk top computers is referred to as byte caching. In byte caching, information is stored in a cache (temporary memory) until needed. Node B sites have cache memories. During a transmission to a user, information including state information is received at cell site and stored in the cache. Since the requesting device (desk top computer) is stationary, all of the information remains in the cell site location with interference or disruption. However, with a mobile device, if the device moved to another cell site location, the information (including state information) in the cache of at the first cell site location would be useless to the user because user is not communicating with a different cell site.
The current technology at the Node B (networks edge) of a cellular network provides caching to fixed location devices like laptops and desktop computers which connect to the Internet via the cellular network. Today, the current technology does not provide services of any kind to mobile devices like IPhones, Androids, iPAds or other cell phones. The reason for this restriction is that: 1) the edge cache state information is not preserved when to mobile device moves from one cell to another, 2) the caches in adjacent cells cannot be synchronized for either macro diversity or cell hand offs, and 3) a hard TCP connection break occurs when a mobile device moves from one cell to another, which disrupts the cache and CDN and in general causes considerable network latency. This remains a need for method and system that would enable to user of it mobile device to move between cell sites without disruption of service or loss of transmitted information. There also remains a need for a byte cache that will work properly at the edges of a cellular network even when the client moves freely among the cells.